1. Field of the Invention
The present invention relates to a popup control system for a portable computer having a setup function and a popup function.
2. Description of the Related Art
Some portable computers have a setup function to alter the system configuration of the individual computer, and a popup function; the former function is generally initiated by a disk operating system. The popup function is to cut a part of the display screen to form a window on the disk operating system or during execution of an application program in response to a specific key input, and display the remaining power of a drive battery or an ON/OFF message for a resume function (which ensures the status of the system when powered off to be resumed when the system is activated again) on the window screen to permit the resume function to be enabled or disabled as needed. This popup function is generally initiated upon depression of a specific key (for example, a function key or an Escape key). Such a portable computer has a programmable interval timer which generates an internal interrupt (software interrupt) for every given time. In response to this internal interrupt, a CPU polls a keyboard controller to determine if any key is depressed. When a specific key instructing the activation of the popup function is depressed, the CPU initiates the routine for a popup process.
Portable computers having such a popup function therefore require longer time for the CPU to attend to the timer interrupt process as compared with computer having no popup functions. If the CPU is executing an application program such as a communication processing, with a high communication rate, the CPU may still be executing the timer interrupt process when it is the time to transmit the next bit. This is likely to cause a bit drop in communication data. This is because the timer interrupt process is performed irrespective of whether the popup function is necessary or not. When the popup function is not used, therefore, wasteful processing intervenes processing in the portable computer, thus lowering the processing speed of the system.